"""author: wangxin
   data: 2021/11/24
   project: 王鑫 容器作业.py
"""

str = input("请输入一个字符串：")
lst = []
for i in str:
    if i in lst:
        print(f"第一个重复的字符为{i}")
        break
    else:
        lst.append(i)
